Normal individuals performed two matching tasks. In one task, semantic processing, synonyms had to be recognized. Half the stimuli were picturable and half were nonpicturable nouns. In this task, recognition of picturable synonyms was found to have hemifield symmetry, whereas recognition of nonpicturable synonyms yielded a left-hemisphere superiority, indicating that semantic matching itself did not reveal equal performance of both hemispheres. It is concluded that picturable synonyms might be recognized either by processes of visual imagery, which pertain to right-hemisphere function, or by their phonological or phonic features, which are processed by the left hemisphere. The other task, shown in previous research to exhibit a left-hemisphere superiority, was to decide if two nouns (homophones) were equally pronounced. Here a distinct left-hemisphere advantage was revealed.Words tachistoscopically presented in the right visual half-field (RVF) are generally easier to recognize than those presented in the left visual half-field (LVF) (Barton, Goodglass, & Shai, 1965; Goodglass & Barton, 1963; Heron, 1957;Mishkin & Forgays, 1952). Kimura (1961) suggested that RVF advantages in word recognition were a consequence of the direct contralateral connections with the language center in the left hemisphere (LH).Most studies have compared laterality effects for single-word recognition as a function of such lexical properties as word length, letter position, frequency of occurrence, concreteness, imageability, or syntactic class (see Searleman, 1977). Several studies have indicated that abstract and low-imageability words show a larger RVF superiority than do concrete or high-imageability words. Ellis and Shepherd (1974) presented 20 abstract and 20 concrete words to normal subjects. Concrete words yielded an insignificant LH advantage and abstract words a significant one. Hines (1976) carried out a similar experiment and observed an interaction between hemispheres and concreteness. The LH superiority was greater for This study was supported in part by research grants from the Holderbank-Stiftung, Switzerland, and from the Stiftung fUr Medizinisch-Biologische Forschung, Switzerland, and in part by a grant from the Centre en Science neurologique of the University of Montreal, Canada. Requests for reprints should be addressed to Manfred Rodel, Neurological Department, University Hospital of Ziirich, Raernistrasse 100, CH-8091 Ziirich, Switzerland.
523abstract words than for concrete words. Marcel and Patterson (1979) provided evidence of a selective disability of the right hemisphere (RH) in dealing with low-imageability words. Yet, conflicting results were found by Hatta (1977) and by Saffran, Bogyo, Schwartz, and Marin (1980), who refuted these tendencies for concrete and abstract kanji characters. Nevertheless, the findings that pointed to an equal recognition of concrete and high-imageability words in left and right hemifields showed that high-frequency, concrete, picturable nouns are more likely to be successfully ana...
